The invention relates to reinforcements for strip structures and more specifically, though not exclusively, to reinforcements for channel-shaped strips such as for sealing, finishing, and guiding purposes and to such strip structures and channel-shaped strips. Such strips may, for example, be used for finishing or sealing the flanges around openings in vehicle bodies or the like, or for supporting, sealing or guiding the edges of window glass.
In use, such strips may be supplied to the vehicle body manufacturer already cut into lengths suited to particular door openings. Such lengths may be joined on themselves to provide a completely closed loop. In either case, it will be appreciated that it is very important that the strip should maintain a substantially constant length once its manufacturing process has been completed. If it undergoes changes in length, then it may be found to be of incorrect length when it comes to be fitted to the vehicle body. If it changes its length after having been fitted to the vehicle body, for example if it shrinks, it will tend to be pulled off the edge flange at corners or bends in the flange and provide an unsightly appearance and ineffective weather seal. Various factors can tend to change the length of the strip. For example, the strip may be subjected to tension while it is being fitted to the edge flange. It will also be subjected to tension during its manufacturing process, and if this causes stretching, then it may shrink by subsequent resiling. Temperature changes may also tend to change its length. Such temperature changes may merely be ambient temperature changes. In addition, however, the sealing strip may be subjected to quite substantial changes in temperature in the case where the vehicle body to which it is fitted is passed through a paint-drying oven.
An object of the invention is to provide an improved reinforcement for a strip structure.
Another object of the invention is to provide an improved channel-shaped strip structure.